HINT: Important order for working - C. A. M:
C = Categories. First - create your categories
A = Articles. Next - create your articles
M = Menu. Next - add your article to your menu

For good information on Categories go to: http://www.siteground.com/tutorials/joomla/joomla-categories.htm

Before you create your first article category all of your articles will be assigned to the Uncategorised category. This is Joomla’s default category and should not be removed.

To make a new category:

• Go to Category Manager > New > Title
• Give the category an appropriate title > Save & Close

NOTE: In Joomla, a category that contains a sub-category is called a parent category. The sub-category is called a child category, although the term sub-category is used as well. It is perfectly OK for a child category to contain child categories of its own. The process of placing child categories within parent categories is called nesting categories.

To create a sub category:

• As above for a New Category
• Add an appropriate Title
• Click the Parent down arrow and choose a Parent from the list.
• Choose alphabetical ascending or descending, by title
• oldest or newest first
• ordering (the order in which the articles appear in the Article Manager) e.g.
  • Android
  • iPad
  • Linux
  • Mac
  • Windows
  • Photography
  • Email & Internet
  • Organisation & Maintenance
  • Workshops

Category Ordering

By default Joomla displays articles on Category/Section Blog or List pages in the order in which you publish them. 

More information on Categories

When creating and assigning categories, you should have a planned structure. As an example, to categorise several Joomla articles on birds, create two article categories called "Animals" and "Plants". Under the "Animals" category, add sub categories called "Birds" and "Mammals". Under the "Birds" category, add 3 articles named "Hawks," "Parrots" and "Sparrows".

This could be expanded even more with specific articles on different species of Hawks, Parrots and Sparrows.

Start with using an "Animal" top Category. Placing the sub categories "Birds" and "Mammals" are under the Animal category, and then a "Hawks," "Parrots" and "Sparrows" sub category under the "Birds" Sub Category as shown.

• Animals
  • Birds
    • Hawks
    • Parrots
    • Sparrows

Now you can create multiple articles in the Hawk, Parrot and Sparrow Categories using the different genus or common names of the specific types of these 3 birds.

Our present categories - sub-categories: